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The ReferenceError
object represents an error when a non-existent variable is referenced.
Syntax
new ReferenceError([message[, fileName[, lineNumber]]])
Parameters
message
- Optional. Human-readable description of the error
fileName
- Optional. The name of the file containing the code that caused the exception
lineNumber
- Optional. The line number of the code that caused the exception
Description
A ReferenceError
is thrown when trying to dereference a variable that has not been declared.
Properties
ReferenceError.prototype
- Allows the addition of properties to an
ReferenceError
object.
ReferenceError
instances
Properties
ReferenceError.prototype.constructor
- Specifies the function that created an instance's prototype.
ReferenceError.prototype.message
- Error message. Although ECMA-262 specifies that
ReferenceError
should provide its ownmessage
property, in SpiderMonkey, it inheritsError.prototype.message
. ReferenceError.prototype.name
- Error name. Inherited from
Error
. ReferenceError.prototype.fileName
- Path to file that raised this error. Inherited from
Error
. ReferenceError.prototype.lineNumber
- Line number in file that raised this error. Inherited from
Error
. ReferenceError.prototype.columnNumber
- Column number in line that raised this error. Inherited from
Error
. ReferenceError.prototype.stack
- Stack trace. Inherited from
Error
.
Methods
Although the ReferenceError
prototype object does not contain any methods of its own, ReferenceError
instances do inherit some methods through the prototype chain.
Examples
Catching a ReferenceError
try { var a = undefinedVariable; } catch (e) { console.log(e instanceof ReferenceError); // true console.log(e.message); // "undefinedVariable is not defined" console.log(e.name); // "ReferenceError" console.log(e.fileName); // "Scratchpad/1" console.log(e.lineNumber); // 2 console.log(e.columnNumber); // 6 console.log(e.stack); // "@Scratchpad/2:2:7\n" }
Creating a ReferenceError
try { throw new ReferenceError('Hello', 'someFile.js', 10); } catch (e) { console.log(e instanceof ReferenceError); // true console.log(e.message); // "Hello" console.log(e.name); // "ReferenceError" console.log(e.fileName); // "someFile.js" console.log(e.lineNumber); // 10 console.log(e.columnNumber); // 0 console.log(e.stack); // "@Scratchpad/2:2:9\n" }
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 3rd Edition (ECMA-262) | Standard | Initial definition. |
ECMAScript 5.1 (ECMA-262) The definition of 'ReferenceError' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'ReferenceError' in that specification. |
Standard | |
ECMAScript Latest Draft (ECMA-262) The definition of 'ReferenceError' in that specification. |
Draft |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
ReferenceError | Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 5.5 | Opera Full support Yes | Safari Full support Yes | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support 1.0 | nodejs Full support Yes |
Legend
- Full support
- Full support